I take 4000 IU of vitamin d3 per day so is vote that you supplement over rather than under. I read a very interesting article about a study done on pregnant women, it claimed that vitamin d3 supplementation of 4000 IU reduced rates of Placenta problems, preeclampsia and preterm labor. I had also read an article (not as soundly supported imo) that being vitamin d deficient during labor caused more painful labors.

I use Garden of Life raw d3 supplements. They kind of taste like farts to be honest but if they absorb well I'll deal.